


Heartache

by Radiant_Shooketh



Category: Fate/Grand Order, Fate/stay night & Related Fandoms, Fate/stay night - All Media Types
Genre: Angst and Feels, Blood and Violence, Despair, Gen, Guilt, Heavy Angst, I entered hell, Mental Anguish, No beta readers I die like a man
Language: English
Status: Completed
Published: 2020-12-08
Updated: 2020-12-08
Packaged: 2021-03-09 20:20:06
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 2,164
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27952205
Author URL: https://archiveofourown.org/users/Radiant_Shooketh/pseuds/Radiant_Shooketh
Summary: So after being recently pulled into Fate/Grand Order hell, I became more interested in Irish myth, especially after seeing how cool Cú Chulainn was in Fate/Stay Night. I wanted to see if there was any fanfics with him and his son Connla and surprisingly, there weren't any except one. That one that I found and read was amazing and so feeling inspired after reading it, wrote this based on Benit149's story "FATE/LAOCH GAN FINSCEAL" as well as their many other Connla stories. Think of this oneshot as a what-if scenario. A bad end story, if you will.Anyway, go check them out and read their story: https://www.fanfiction.net/s/12930929/1/Fate-Laoch-Gan-Finsceal
Kudos: 1





	Heartache

**Author's Note:**

> Just keep in mind while reading, Connla got the genderbent treatment here. It's how it was written in Benit's stories too so if you're not happy with that, don't read this. Anyway, enjoy!

The man with blue hair was floating in a pure void of nothingness, curled up in a fetal position with his head down. There was literally nothing in the location that he was currently in. He wasn’t somewhere on Earth, nor in the Throne, or even in some alternate universe. He was just… nowhere at all. He was outside time and space itself, and he didn’t know why. He just floated there in solitude, with no one and nothing to disturb him. The silence was so deafening, it felt like he was about to go crazy. He must have gone crazy a long time ago, surely. 

Then, the scene changed. 

He was suddenly standing up, his trusty red spear in his hands. The background was an eerie crimson, for some reason. Something suddenly whizzed past him. A blurry figure of green wind that was too fast for his eyes to catch. What was going on? The figure whizzed past him again, though much closer than before. They were approaching him fast. Suddenly, he got a better look at the figure, though their face was blurred out for some reason. A small individual with purple hair tied in a ponytail wearing a mint green bodysuit with runic protection on it that was very similar to his own, a white skirt over it, thick brown gloves, and knee high boots. Something in the back of his mind told him that this person was very familiar and important to him. His body and mind practically screamed at him not to attack them but the fear of the unknown told him otherwise and he had to defend himself. They are the one attacking him, after all.    
  
They wielded a leaf-bladed spear and using it, they vaulted over him, twisting their body with precision, stabbed down and aimed for his head, going for the kill. On pure instinct, the man blocked their blow with his spear and threw them off. Yelling, he charged at them and giving them no time to react at all, stabbed Gáe Bolg into their small body, the spear piercing their heart and the tip protruding out their small chest. The figure let out a pained cry, and the man realized his victim was but a child. A girl, in fact. He didn’t like killing innocent people, especially if they were women. This was must worse since they were but a small child. He swiftly pulled his spear from their chest and watched a copious amount of blood flooded from the wound and gathered in a large red puddle at their feet. Blood dripped from his spear, but he paid no mind to it. The figure remained standing on their feet surprisingly, and that shocked him. Their face was now much clearer to the man, and his eyes widened in horror, his throat tightening in despair and an unspeakable sadness and shock was seen in his eyes. No, it couldn't be…

“Father… do you really hate me that much?” The little girl asked him, a hollow look in her brown eyes. She smiled at him and blood seeped from her mouth. It was truly a nightmarish sight. The curse of Gáe Bolg coursed through her, and he saw streams of the blue barbs encroaching her small face. Her body fell limp in his arms and he caught her, holding her tiny body close to his chest, screaming in rage and horror. 

_ No, not again! What is happening? Why am I seeing this?!  _

The scene changed again. With the girl’s body now gone, the man was crouched down holding his head in his hands. He wanted to block everything out from his mind. The memory of murdering his beloved daughter was still fresh in his soul and heart, and it ate him up from the inside like poison. Something suddenly materialized beside him. A dark black-reddish sludge with no form stood up near him and leaned close to his ear.

“You did that, Cú Chulainn. You killed her.” Despite not having any facial features, he could hear the smile in its voice as it mocked him. He materialized his spear and stabbed at the sludge in rage, veins bulging in his face and the inside of his eyes.

“SHUT THE FUCK UP!”    
  


The sludge wasn’t harmed or anything. The tip of the spear that was wedged in the sludge came out the other side and when he pulled his spear out, the sludge simply shifted to correct its form. “Such fighting spirit. You wouldn’t be Cú Chulainn otherwise,” the sludge mocked him again.

Cú Chulainn turned away from the sludge in disdain, glaring at the floor. “There’s no need to show me all this. I know what I did to her. You think I’m not suffering from my actions that I committed in life?” There’s no words describing the amount of grief and trauma he is experiencing at that moment, and everyday after her death. Especially when he was summoned in Holy Grail Wars to fight in. He was always summoned to wars, but she was never there to accompany him, and that was all his fault. No parent should have to bury their own child and yet on that fateful day, Cú and his comrades buried Connla after he fought her in a misunderstanding. Children were supposed to outlive their parents, growing up happy and fulfilled and healthy. Connla never got the chance to, thanks to him and Aífe. 

The sludge disappeared and next to Cú Chulainn was an illusion of Connla. He stared at her with horror in his eyes as he looked at her chest, which had a gaping hole right where he stabbed at it with Gáe Bolg. He shut his eyes in agony, kneeling down on the ground. 

“Stop it. Please, just stop…”    
  


“When I turned 7, I left Scotland and journeyed to Ireland in excitement and anticipation to find you.” The girl twisted the ring on her thumbs. A symbol of promise between her and Cú Chulainn as parent and child that he left for her, and proof of their bond and lineage. Or so she thought. “No words could describe how excited I was to meet you. The great and mighty Cú Chulainn, my father. I couldn’t believe it at first when Mother told me. But what did I find? You were enjoying the company of your beloved wife and all your friends and comrades. Where were you all 7 years of my miserable life, Father? I suffered at the abusive whims of Mother, all while you were enjoying your life back in Ulster!”

“That’s… That’s not true! I had a war to fight. That’s why I left Aífe with that ring. I told her to give you that ring when you came of age so that you can find me in Ireland…”

“Liar! You abandoned me, Father. You abandoned us! Why couldn’t you have waited until I was born and then taken me with you back to Ulster, huh?! I never asked to be born, and Mother never asked to have me. And in a fleeting moment of lust… You just had to…” The girl twisted her ring in anger and took it off her thumb. “You never loved me, and Mother never loved me. No one ever loved me! I was made to be a weapon, and nothing more!”

“That’s not true!” Cú grabbed her hands, which were very much real and looked at her, but she kept her eyes averted from his desperate gaze. “Connla, look at me. Please.” After his pleading, she finally did meet his red eyes with a hard glare. “Not a day goes by where I think about all the things we could have accomplished together as both warriors, and humans on this planet. Not a day goes by where I regret meeting you that day under those unfortunate circumstances.” Damn that Aífe for putting those 3 geasa upon Connla like that. Of course, that was all part of her revenge plan against him so that he can be left in agony and despair for the rest of his short life.

“Nothing you say now can change the fact that you murdered me, and all for the glory and honour of Ulster. You truly are a despicable man, Cú Chulainn. I wish from all the bottom of my heart that you never were my father,” she hissed with venom in her voice. That left him stunned in silence, and him feeling incredibly hurt. It felt like he was stabbed with his own spear right in his heart. Leaving him in shock, Connla walked away from her father. She stopped for a brief moment, here gaze down as she stared at the ring that she took off. Glaring at it, she suddenly whirled around and chucked it with remarkable aim at Cú, the ring bounced painfully off of his chest. “You can have that back, I don’t want it. That measly ring did nothing to protect me from Mother. It never held any significance for me. It’s useless! That ring did absolutely nothing for me…” 

Connla’s form dissipated in a mint green smoke. Cú Chulainn rushed forward and reached his hand out just as his daughter disappeared. “No wait, come back! Please!” He sunk to his knees, still holding onto the golden ring that was originally hers in his right hand. “Don’t leave me alone again...” he whispered softly. He curled into a ball again, staring at the ring with empty eyes. 

“Truly pathetic,” the voice of the sludge chortled at him as it swirled to life beside him. “All the grief and sadness and agony and hatred and self-loathing are eating away at your heart, Cú Chulainn. You truly are a pathetic man. What kind of father are you? You know that she’s right. You could have waited until she was born before bringing her back with you to Ulster. You just left her there at the mercy of an abusive mother. You could never hope to imagine all the pain and suffering she endured at the hands of Aífe. She was brutal, and merciless towards her own daughter. You could have saved her from all that, but you abandoned her instead. What kind of father are you? You are a monster. You are truly despicable and perhaps much worse than Aífe herself. You participated in Connla’s suffering just as much as her mother did. You are just as guilty if not more for causing Connla so much pain and grief.” 

“... You think I don’t already know that?” Cú muttered at the sludge. He stared at the ring, tracing the red angular markings on it with his thumb. “But I had a war to fight. I had to make sure that my child could enter Ulster when it was peaceful.”

“Nothing but pathetic excuses from a pathetic man. You could have let your wife take care of Connla whilst you fought Medb’s forces, but you did not. This is all an appropriate punishment for you. You deserve all this suffering for making your child experience no thing a child should have had to experience in their life.”    
  


“...” 

“Father, you could have saved me. So, why didn’t you?” Cú heard Connla’s disembodied voice ask him from somewhere within the darkness. Grief welled up in his chest again.   
  


“I’m sorry.” What more could he say? He let her down, after all. What could he say to her that would make her forgive him?    
  


“I’ll never forgive you, you know,” Connla replied calmly, as if reading his thoughts. All he wanted was to see her again under normal circumstances. All he wanted was to embrace here tightly and never let her go. He would then actually raise her and treat her well. She didn’t have to live as a warrior. He wanted her to live a normal and happy life with no worries. But that could never happen. 

“You wish for the sweet embrace of permanent death, do you not? Well, that will never happen. As long as you remain Cú Chulainn, you will always be a Heroic Spirit who will answer the call from a Master somewhere. There’s nothing you can do to escape from your feelings,” the demonic sludge told him. 

Cú Chulainn’s mind eventually deteriorated. After relieving the madness of killing his beloved child, he went from a noble and proud warrior to that of a demon and went through a hideous transformation. A spiked tail suddenly exploded from his hind, and black and red scales covered his entire body. On his face, strange red marking decorated his face, just below his eyes. His chest and abdomen now exposed were covered in strange red tattoos. He grit his now very sharp and pointy teeth in pain as he grasped his head in his clawed hands. He will forever remain in this void, thinking of the sin that he committed in his life while wishing someone could come and end his eternal suffering. 


End file.
